相关论文: Radio Transients from Newborn Black Holes
We propose a new type of electromagnetic transients associated with the birth of binary black holes (BBHs), which may lead to merger events accompanied by gravitational waves in $\sim0.1-1$ Gyr. We consider the newborn BBHs formed through…
Newborn black holes in collapsing massive stars can be accompanied by a fallback disk. The accretion rate is typically super-Eddington and strong disk outflows are expected. Such outflows could be directly observed in some failed explosions…
Most black holes (BHs) formed in collapsing stars have low spin, though some are expected to acquire a magnetic accretion disk during the collapse. While such BH disks can launch magnetically driven winds, their physics and observational…
We discuss the electromagnetic radiation from newborn binary black holes (BBHs). As a consequence of the evolution of massive stellar binaries, a binary consisting of a primary black hole (BH) and a secondary Wolf-Rayet star is expected as…
Recently, the direct detection of gravitational waves from black hole (BH) mergers was announced by the Advanced LIGO Collaboration. Multi-messenger counterparts of stellar-mass BH mergers are of interest, and it had been suggested that a…
Most black holes (BHs) will absorb a neutron star (NS) companion fully intact, without tidal disruption, suggesting the pair will remain dark to telescopes. Even without tidal disruption, electromagnetic luminosity is generated from the…
We have simulated the collapse and evolution of the core of a solar-metallicity 40-M$_{\odot}$ star and find that it explodes vigorously by the neutrino mechanism. This despite its very high "compactness". Within $\sim$1.5 seconds of…
We investigate the properties of accretion flows onto a black hole (BH) with a mass of $M_{\rm BH}$ embedded in an initially uniform gas cloud with a density of $n_{\infty}$ in order to study rapid growth of BHs in the early Universe. In…
The observations and theory of the exciting new class of galactic black hole X-ray transients is reviewed. Seven of these systems have measured mass functions or mass estimates in excess of stable neutron stars, making them excellent black…
The BH masses and the Eddington ratios for a sample of 65 young radio galaxies [27 GPS and 38 CSS sources] are estimated by various methods. We find that the average BH mass of these young radio galaxies is <log M_bh>=8.3, which is less…
Outflows are inevitably driven from the disk if the vertical component of the black hole (BH) gravity cannot resist the radiation force. We derive the mass loss rate in the outflows by solving a dynamical equation for the vertical gas…
Using recently published estimates - based on high spatial resolution spectroscopy - of the mass M_{BH} of nuclear black holes for a sample of nearby galaxies, we explore the dependence of galaxy nucleus emissivity at various wavelengths on…
The origin of spin of low-mass supermassive black hole (SMBH) is still a puzzle at present. We here report a study on the host galaxies of a sample of radio-selected nearby ($z<0.05$) Seyfert 2 galaxies with a BH mass of $10^{6-7} M_\odot$.…
Radio emission from the high- and super-Eddington accreting active galactic nuclei (AGNs) has various origins: a persistent jet, the magnetized corona and the wind-like outflows. It is now still unclear which is the leading mechanism…
The recent discovery of a 4 $\times$ 10$^7$ M$_{\odot}$ black hole (BH) in UHZ1 at $z =$ 10.3, just 450 Myr after the big bang, suggests that the seeds of the first quasars may have been direct-collapse black holes (DCBHs) from the collapse…
We explore the formation process of a black hole (BH) through the pair-instability collapse of a rotating Population III very massive star in axisymmetric numerical relativity. As the initial condition, we employ a progenitor star which is…
We perform two-dimensional radiation hydrodynamical simulations of accretion flows onto a black hole (BH) with a mass of $10^3\leq M_{\rm BH}/M_{\odot} \lesssim 10^6$ in order to study rapid growth of BHs in the early Universe. For…
We investigate mass ejection from accretion disks formed in mergers of black holes (BHs) and neutron stars (NSs). The third observing run of the LIGO/Virgo interferometers provided BH-NS candidate events that yielded no electromagnetic (EM)…
One possible scenario for the formation of massive black holes (BHs) in the early Universe is from the direct collapse of primordial gas in atomic-cooling dark matter haloes in which the gas is unable to cool efficiently via molecular…
It has long been expected that some massive stars produce stellar mass black holes (BHs) upon death. Unfortunately, the observational signature of such events has been unclear. It has even been suggested that the result may be an "unnova,"…